Abstract: A housing-debt contract is an agreement to guarantee private lending through signing a house sale and purchase contract. Despite its enormous practices， there is still dispute on the effectiveness and ineffectivenessin terms of the clause validity. What is worse， Article 24 of “The provisions of the supreme people’s court on the application of law in private lending cases”adopts an avoidance attitude towards this issue. The validity of house-debtcontracts could not be denied simply because there is no false intention or conspiracy， which is different from fluidity contracts. By analyzing the nature of the clauses for house-debt contracts， such explanations as alienation guarantee， after-alienation guarantee， contract with termination and conditional sale contract are questionable. A house-debt contract is essentially a pre-contract for datio in solutum，and in accordance with the legal cases， the creditors can rule out the third person's claim for the housing price， i.e.， the creditor shall enjoy the right of property expectation， which may provide useful reference for setting such disputes in judicial practices.

Key words: housing-debt contract, sale-on term, loan contract, pre-contract for datio in solutum